Adhesion of leukocytes to the endothelium represents a fundamental, early event in a wide variety of inflammatory conditions, autoimmune disorders and bacterial and viral infections. Leukocyte recruitment to endothelium is mediated in part by the inducible expression of adhesion molecules on the surface of endothelial cells that interact with counterreceptors on immune cells. Endothelial cells determine which types of leukocytes are recruited by selectively expressing specific adhesion molecules, such as vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), and E-selectin. VCAM-1 binds to the integrin VLA-4 expressed on lymphocytes, monocytes, macrophages, eosinophils, and basophils but not neutrophils. This interaction facilitates the firm adhesion of these leukocytes to the endothelium. VCAM-1 is an inducible gene that is not expressed, or expressed at very low levels, in normal tissues. VCAM-1 is upregulated in a number of inflammatory diseases, including arthritis (including rheumatoid arthritis), asthma, dermatitis, psoriasis, cystic fibrosis, post transplantation late and chronic solid organ rejection, multiple sclerosis, systemic lupus erythematosis, inflammatory bowel diseases, autoimmune diabetes, diabetic retinopathy, rhinitis, ischemia-reperfusion injury, post-angioplasty restenosis, chronic obstructive pulmonary disease (COPD), glomerulonephritis, Graves disease, gastrointestinal allergies, conjunctivitis, atherosclerosis, coronary artery disease, angina and small artery disease.
Coronary heart disease (CHD), primarily as a result of atherosclerosis, remains the leading cause of death in industrialized countries. Atherosclerosis is a disease characterized by vascular inflammation, deposition of lipids in the arterial vessel wall and smooth muscle cell proliferation resulting in a narrowing of the vessel passages. In advanced stages of the disease atherosclerotic lesions can become unstable resulting in plaque rupture, thrombosis, myocardial infarction and ischemic heart disease. It is now well accepted that the initiating events in atherosclerosis are local injury to the arterial endothelium that results in the induction of VCAM-1 and recruitment of mononuclear leukocytes that express the integrin counterreceptor, VLA-4, (O'Brien, et al., J. Clin. Invest., 92: 945–951, 1993). Subsequent conversion of leukocytes to foamy macrophages results in the synthesis of a wide variety of inflammatory cytokines, growth factors, and chemoattractants that help propagate formation of the mature atheromatous plaque by further inducing endothelial activation, leukocyte recruitment, smooth muscle cell proliferation, and extracellular matrix deposition. Pharmacological inhibition of VCAM-1 expression has been shown to inhibit atherosclerosis in several animal models (Sundell et al., Circulation, 100: 42, 1999). A monoclonal antibody against VCAM-1 has also been shown to inhibit neointimal formation in a mouse model of arterial wall injury (Oguchi, S., et al., Arterioscler. Thromb. Vasc. Biol., 20: 1729–1736, 2000).
Asthma, which is increasing in prevalence and morbidity world-wide, is a chronic inflammatory disease characterized by lung eosinophilia and bronchial hyperreactivity. The interaction between VCAM-1 on lung endothelial cells and VLA-4, which is the integrin counterreceptor expressed on eosinophils, is thought to be important for selective eosinophil recruitment. Eosinophils have been considered an important effector cell in the pathogenesis of asthma and other allergic diseases. Activated eosinophils release proteins such as major basic protein (MBP) that have been demonstrated to induce bronchial hyperreactivity, one of the defining criteria of asthma (Bousquot, et al., N. Engl. J. Med., 323: 1033–1039, 1990). It has been demonstrated that VCAM-1 is markedly upregulated on human bronchial vascular endothelium of subjects with asthma who have air flow limitation, when compared with subjects without asthma (Pilewski, et al., Am. J. Respir. Cell Mol. Biol., 12, 1–3, 1995; Ohkawara, Y., et al., Am. J. Respir. Cell Mol. Biol., 12, 4–12, 1995; Gosset, P., et al., Int. Arch. Allergy Immunol. 106: 69–77, 1995; Hacken, N. H., et al., Clin. Exp. Allergy, 28 (12): 1518–1525, 1998). An elevation in serum soluble VCAM-1 levels has also been demonstrated in patients undergoing a bronchial asthma attack compared with levels under stable conditions (Montefort, S., Koizumi, A., Clin. Exp. Immunol., 101: 468–73, 1995). Several animal studies further demonstrate a spatial and temporal association between VCAM-1 and asthma. In a mouse model of allergic asthma, VCAM-1 expression was shown to be induced by allergen challenge, and administration of an anti-VCAM-1 antibody was effective in inhibiting eosinophil infiltration that occurred in this model (Metzger, W. J., et al., J. Allergy Clin. Immunol., 93: 183, 1994). Further evidence for the importance of VCAM-1 in allergic asthma comes from work in IL-12 knockout mice. IL-12 knockout mice had fewer eosinophils and VCAM-1 expression than wildtype mice; however, administration of recombinant IL-12 at the time of ova sensitization and challenge restored lung VCAM-1 expression and eosinophilia (Wang, S., et al., J. Immunol., 166:2741–2749, 2001). There are several examples where blocking the integrin receptors for VCAM-1 have had positive effects on animal models of asthma (Rabb et al., Am. J. Respir. Care Med. 149: 1186–1191, 1994; Abraham, W, et al., Am. J. Respir. Crit. Care Med. 156: 696–703. 1997) further demonstrating the importance of VCAM-1/VLA-4 interactions in allergic inflammation. Eosinophils are also important effector cells in allergic rhinitis. VCAM-1 has been demonstrated to be upregulated 24 hrs after nasal allergen provocation in patients with seasonal allergic rhinitis but not in normal subjects (Braunstahl, G. J., et al., J. Allergy Clin. Immunol., 107: 469–476, 2001).
Rheumatoid arthritis (RA) is a clinical syndrome of unknown cause characterized by symmetric, polyarticular inflammation of synovial-lined joints. The role of adhesion molecules in the pathogenesis of RA has also been well documented, and VCAM-1 expression on synovial fibroblasts is a clinical hallmark of RA (Li, P., et al., J. Immunol. 164: 5990–7, 2000). VLA-4/VCAM-1 interactions may be the predominant mechanism for recruitment of leukocytes to the synovium (Dinther-Janssen, et al., J. Immunol. 147: 4207–4210, 1991; Issekeutz and Issekeutz, Clin. Immunol. Immunopathol. 61:436–447, 1991; Morales-Ducret et al., J. Immunol. 149:1424–1431, 1992; Postigo et al., J. Clin. Invest. 89:1445–1452, 1992; Matsuyama, T., et al, Hum. Cell, 9: 187–192, 1996). In support of this, increased VCAM-1 expression has been found in RA synovial tissue compared with osteoarthritis and control tissue (Wilkinson et al., Lab. Invest. 69:82–88, 1993; Furuzawa-Carballeda, J., et al., Scand. J. Immunol. 50: 215–222; 1999). Soluble VCAM-1 is higher in RA patients than in control subjects (Kolopp-Sarda, M. N., et al., Clin. Exp. Rheumatol. 19: 165–70, 2001). Soluble VCAM-1 has been shown to be chemotactic for T cells (Kitani, A., et al., J. Immun. 161: 4931–8, 1998), and in addition to being a possible diagnostic marker for RA, may contribute to its pathogenesis by inducing migration and recruitment of T cells. VCAM-1 expressed on fibroblast-like synoviocytes has also been implicated in enhanced survival of activated synovial fluid B cells (Marinova, Mutafcheia, L., Arthritis Rheum. 43: 638–644, 2000) that may further contribute to RA pathogenesis.
Chronic inflammation and accompanying vascular complications and organ damage characterize systemic lupus erythematosis (SLE). Recent studies suggest that VCAM-1 plays a role in SLE. Expression of VCAM-1 is increased on dermal vessel endothelial cells in patients with active systematic lupus erythematosus (Jones, S. M., British J. Dermatol. 135: 678–686, 1996) and correlates with increased disease severity (Belmont et al., Arthritis Rheum. 37:376–383, 1994). SLE muscle samples with perivascular infiltrate have greater endothelial cell expression of VCAM-1 compared with SLE patients without a perivascular infiltrate or with control samples (Pallis et al., Ann. Rheum. Dis. 52:667–671, 1993). Increased expression of VCAM-1 has also been demonstrated in kidneys of lupus-prone MRL/lpr mice compared to nonautoimmune strains and its expression increased with disease severity (McHale, J. F., et al., J. Immunol. 163: 3993–4000, 1999). VCAM-1 expression on mesangial cells in vitro can be stimulated by IL-1, TNF-α, and INFγ exposure as well as by anti-endothelial cell IgG fraction and anti-DNA autoantibodies from SLE patients (Wuthrich, Kidney Int. 42: 903–914, 1992; Papa, N. D., et al., Lupus, 8: 423–429, 1999; Lai, K. N., et al., Clin Immunol Immunopathol, 81: 229–238, 1996). Furthermore, soluble VCAM-1 is higher in SLE patients than in normal subjects (Mrowka, C., et al., Clin. Nephrol. 43: 288–296, 1995; Baraczka, K., et al., Acta. Neurol. Scand. 99: 95–99, 1999; Kaplanski, G., et al., Arthritis Rheumol. 43: 55–64, 2000; Ikeda, Y., Lupus, 7: 347–354, 1998) and correlates with disease activity (Scudla, V., Vnitr. Lek., 43: 307–311, 1997).
Increased VCAM-1 expression has also been demonstrated in solid organ transplant rejection. Acute transplant rejection occurs when the transplant recipient recognizes the grafted organ as “non-self” and mounts an immune response characterized by massive infiltration of immune cells, edema, and hemorrage that result in the death of the transplanted organ. Acute rejection occurs in a matter of hours or days and has been correlated with increased levels of VCAM-1 in tissues and in plasma (Tanio et al., Circulation, 89:1760–1768, 1994; Cosimi et al., J. Immunol. 144: 4604–4612, 1990; Pelletier, R., et al., Transplantation, 55: 315, 1992). A monoclonal antibody to VCAM-1 has been shown to inhibit cardiac allograft rejection in mice (Pelletier, R., J. Immunol., 149: 2473–2481, 1992; Pelletier, R., et al., Transplantation Proceedings, 25: 839–841, 1993; Orosz, C. G., et al., J. Heart and Lung Transplantation, 16: 889–904, 1997) and when given for 20 days can cause complete inhibition of rejection and long-term graft acceptance (Orosz C. G., et al., Transplantation, 56: 453–460, 1993). Chronic graft rejection also known as allograft vasculopathy is distinct from acute transplant rejection and is a leading cause of late graft loss after renal and heart transplantation. Histologically it is characterized by concentric neointimal growth within vessels that is largely due to smooth muscle migration and proliferation. It is thought to be the result of endothelial damage brought about by several factors including: ischemia-reperfusion injury, immune complexes, hypertension, hyperlipidemia and viruses. All of these factors have been associated with induction of VCAM-1 in endothelial cells. There is also a strong correlation of soluble and tissue VCAM-1 levels with chronic rejection (Boratynska, M., Pol. Arch. Med. Wewn, 100: 410–410, 1998; Zembala, M., et al., Ann. Transplant. 2: 16–9, 1998; Solez K., et al., Kidney International., 51: 1476–1480, 1997; Koskinen P. K., et al., Circulation, 95: 191–6, 1997).
Multiple sclerosis is a common demyelinating disorder of the central nervous system, causing patches of sclerosis (plaques) in the brain and spinal cord. It occurs in young adults and has protean clinical manifestations. It is well documented that VCAM-1 is expressed on brain microvascular endothelial cells in active lesions of multiple sclerosis (Lee S. J., et al., J. Neuroimmunol., 98: 77–88, 1998). Experimental therapy of experimental autoimmune encephalomyelitis, which is an animal model for; multiple sclerosis, using antibodies against several adhesion molecules, including VCAM-1, clearly shows that adhesion molecules are critical for the pathogenesis of the disease (Benveniste et al., J. Neuroimmunol. 98:77–88, 1999). A time and dose dependent expression of VCAM-1 and release of soluble VCAM-1 were detected in cultures of human cerebral endothelial cells induced by TNFα, but not in peripheral blood mononuclear cells (Kallmann et al., Brain, 123:687–697, 2000). Clinical data also show that adhesion molecules in blood and cerebrospinal fluid are up-regulated throughout the clinical spectrum of multiple sclerosis (Baraczka, K., et al., Acta. Neurol. Scand. 99: 95–99, 1999; Reickmann, P., et al., Mult. Scler., 4: 178–182, 1998; Frigerio, S., et al., J. Neuroimmunol., 87: 88–93, 1998) supporting the notion that therapies which interfere with cell adhesion molecules such as VCAM-1 may be beneficial in modifying this disease (Elovaara et al., Arch. Neurol. 57:546–551, 2000).
Diabetes mellitus is a metabolic disease in which carbohydrate utilization is reduced and that of lipid and protein is enhanced. Evidence has accumulated that increased levels of adhesion molecules may play a functional pathophysiological role in diabetes (Wagner and Jilma, Hormone and Metabolic Research, 29: 627–630, 1997; Kado, S., Diabetes Res. Clin. Pract., 46: 143–8, 1999). It is caused by an absolute or relative deficiency of insulin and is characterized by chronic hyperglycemia, glycosuria, water and electrolyte loss, ketoacidosis, and coma. Elevated circulating adhesion molecules including VCAM-1 have been detected in patients with diabetes and in experimental models of diabetes in animals (Lorini et al., Hormone Research, 48: 153, 1997; Otsuki et al., Diabetologia, 40: A440, 1997; Hart et al., FASEB J. 11:A340, 1997; Albertini et al., Diabetologia, 39: A240, 1996; Wagner et al., Diabetologia, 39: A205, 1996; Enghofer et al., Diabetologia, 39: A97, 1996; Koga M., Diabet. Med., 15: 661–667, 1998). In addition, complications of diabetes often include peripheral vasculopathies such as diabetic retinopathy and diabetic nephropathy. It is believed that adhesion of leukocytes to the peripheral vasculature plays a central role in the vasculopathies often associated with diabetes.
Crohn's disease, also known as regional enteritis, is a subacute chronic inflammatory condition of unknown cause, involving the internal ileum and less frequently other parts of the gastrointestinal tract. It is characterized by patchy deep ulcers that may cause fistulas, and narrowing and thickening of the bowel by fibrosis and lymphocytic infiltration. Ulcerative colitis is a chronic disease of unknown cause characterized by ulceration of the colon and rectum, with rectal bleeding, mucosal crypt abscesses, inflammatory pseudopolyps, abdominal pain, and diarrhea. It has been reported that serum VCAM-1 reflects the grade of intestinal inflammation in patients with Crohn's disease or ulcerative colitis (Jones, et al., Gut, 36: 724–30, 1995; Goggins et al., Gastroenterology, 108: A825, 1995; Goeke and Manns, Gastroenterology, 106: A689, 1994; Goeke et al., J. Gasterokenterol. 32:480–486, 1997; Loftus et al., Gastroenterology, 108: A684, 1995; Tahami et al., Gastroenterology, 118: A344, 2000). Antibodies to VCAM-1 have been shown to ameliorate experimentally-induced colitis in mice (Soriano, A., Lab. Invest. 80: 1541–1551, 2000).
Psoriasis is a chronic skin disease characterized by erythematous scaling plaques as a result of keratinocyte hyperplasia, influx of immune cells and endothelial activation (Nickoloff, B. J., et al., J. Invest. Dermatol., 127: 871–884, 1991). VCAM-1 is upregulated in psoriatic skin as compared to normal skin (Groves, R. W., J. Am. Acad. Dermatol., 29: 67–72, 1993; Uyemura, K., et al., J. Invest. Dermatol. 101: 701–705, 1993) and levels of circulating VCAM-1 correlate with disease activity (Schopf, R. E., Br. J. Dermatol., 128: 34–7, 1993).
Given that VCAM-1 is a mediator of chronic inflammatory disorders, it is a goal of the present work to identify new compounds, compositions and methods that can inhibit the expression of VCAM-1. A more general goal is to identify selective compounds and methods for suppressing the expression of redox sensitive genes or activating redox sensitive genes that are suppressed. An even more general goal is to identify selective compounds, pharmaceutical compositions and methods of using the compounds for the treatment of inflammatory diseases.
It is therefore an object of the present invention to provide new compounds for the treatment of disorders mediated by VCAM-1.
It is also an object to provide new pharmaceutical compositions for the treatment of diseases and disorders mediated by the expression of VCAM-1.
It is a further object of the invention to provide compounds and methods of treating disorders and diseases mediated by VCAM-1, including cardiovascular and inflammatory diseases.
It is another object of the invention to provide compounds, compositions and methods to treat arthritis.
Another object of the invention is to provide compounds, compositions and methods to treat rheumatoid arthritis. The inventions compounds, compositions and methods are also suitable as disease modifying anti-rheumatoid arthritis drugs (DMARDs).
It is yet another object of the invention to provide compounds, compositions and methods to treat asthma.
It is another object of the invention to provide compounds, methods and compositions to inhibit the progression of atherosclerosis.
It is still another object of the invention to provide compounds, compositions, and methods to treat or prevent transplant rejection.
It is a further object of the present invention to provide compounds, methods and compositions for the treatment of lupus.
It is a further object of the present invention to provide compounds, methods and compositions for the treatment of inflammatory bowel disease.
It is a further object of the present invention to provide compounds, methods and compositions for the treatment of autoimmune diabetes.
It is a further object of the present invention to provide compounds, methods and compositions for the treatment of multiple sclerosis.
It is a further object of the present invention to provide compounds, methods and compositions for the treatment of diabetic retinopathy.
It is a further object of the present invention to provide compounds, methods and compositions for the treatment of diabetic nephropathy.
It is a further object of the present invention to provide compounds, methods and compositions for the treatment of diabetic vasculopathy.
It is a further object of the present invention to provide compounds, methods and compositions for the treatment of rhinitis.
It is a further object of the present invention to provide compounds, methods and compositions for the treatment of ischemia-reperfusion injury.
It is a further object of the present invention to provide compounds, methods and compositions for the treatment of post-angioplasty restenosis.
It is a further object of the present invention to provide compounds, methods and compositions for the treatment of chronic obstructive pulmonary disease (COPD).
It is a further object of the present invention to provide compounds, methods and compositions for the treatment of glomerulonephritis.
It is a further object of the present invention to provide compounds, methods and compositions for the treatment of Graves disease.
It is a further object of the present invention to provide compounds, methods and compositions for the treatment of gastrointestinal allergies.
It is a further object of the present invention to provide compounds, methods and compositions for the treatment of conjunctivitis.
It is a further object of the present invention to provide compounds, methods and compositions for the treatment of dermatitis.
It is a further object of the present invention to provide compounds, methods and compositions for the treatment of psoriasis.